The present invention relates to a temporary fixing structure for tubular bodies.
In recent years, tanks for heat exchangers such as radiator and condenser are made of aluminum. Such tanks comprise an aluminum tank main body and an aluminum pipe brazed thereto for serving as a cooling water or coolant supplying or discharging tube.
Brazing of the pipe to the tank main body is carried out such that after temporarily fixing the pipe to the tank main body, the assembly is coated with a noncorrosive flux, and then subjected to heat treatment in a brazing furnace.
As will be described in detail later, a typical temporary fixing structure for the pipe to the tank main body is carried out by calking a protrusion formed at the head of an end portion of the pipe.
However, the typical temporary fixing structure presents a problem of requiring a special jig and enormous man-hours for calking the protrusion formed at the head of an end portion of the pipe.
Moreover, when forming a mounting hole in a flat mounting surface of the tank main body through, e.g. punch working, the mounting surface is bent inward with the mounting hole as center. Thus, after temporary fixing of the pipe to the tank main body, a clearance is formed between a flange of the pipe and the mounting surface of the tank main body, which may make sure brazing of the flange to the mounting surface difficult.
It is, therefore, an object of the present invention to provide a temporary fixing structure for tubular bodies, which allows easy and secure temporary fixing of tubular bodies with no special jig and less man-hours.
The present invention provides generally a structure which comprises: a first tubular body, the first tubular body having a surface with a hole; a second tubular body, the second tubular body having an end portion inserted in the hole of the first tubular body; a flange arranged at the end portion of the second tubular body, the flange including a flat portion abutting on the surface of the first tubular body; recesses formed with the hole of the first tubular body, the recesses facing each other, wherein a diameter of the hole extending along the recesses is smaller than that of the flange; and protrusions arranged at a head of the end portion of the second tubular body, wherein a spacing between each protrusion and the flange is substantially equal to a thickness of the surface of the first tubular body, wherein the protrusions are arranged inside the fist tubular body through the recesses, wherein the second tubular body is turned with respect to the first tubular body to bring the flat portion of the flange into close contact with the surface of the first tubular body.
A main feature of the present invention is to provide a structure which comprises: a first tubular body, the first tubular body having a surface with a hole; a second tubular body, the second tubular body having an end portion inserted in the hole of the first tubular body; a flange arranged at the end portion of the second tubular body, the flange including a flat portion abutting on the surface of the first tubular body; a brazing material placed on at least one of the flat portion of the flange and a portion of the face of the first tubular body corresponding to the flat portion; recesses formed with the hole of the first tubular body, the recesses facing each other, wherein a diameter of the hole extending along the recesses is smaller than that of the flange; and protrusions arranged at a head of the end portion of the second tubular body, wherein a spacing between each protrusion and the flange is substantially equal to a thickness of the surface of the first tubular body, wherein the protrusions are arranged inside the fist tubular body through the recesses, wherein the second tubular body is turned with respect to the first tubular body to bring the flat portion of the flange into close contact with the surface of the first tubular body.